China and Russia will hold joint military exercises in September in the disputed South China Sea, China's military announced on Thursday.

The joint drills by the two countries will take place on land and at sea and will not target any third party, China's Defense Ministry spokesman Yang Yujun said, according to the state-run Xinhua News Agency. The drills are designed to improve the China-Russia strategic partnership and their ability to jointly deal with maritime security threats, Yang said.

The announcement came one day after a meeting of 10 South Asia-Pacific and South East Asian Nations (ASEAN), ended without a joint rebuke of China’s claim to islands and rocks in the disputed waterway.

A rebuke was expected after an international tribunal ruled this month against China’s vast territorial claims to the region in a case brought by the Philippines.